Iran has warned that it will prosecute five British sailors if it is proven they had "evil intentions" when their 60-foot racing yacht entered its waters, in what Britain says was an innocent case of a vessel accidentally going astray in the Gulf.

London was trying to keep the incident from getting tangled up in politics.

David Miliband, Britain's foreign minister, has insisted this incident has nothing to do with politics - and that it should be ended without anger or confrontation.

The five men were detained by the Iranian navy on November 25 after their racing yacht apparently drifted into Iranian territorial waters, British officials have said. The vessel was travelling from Bahrain to Dubai.

The yacht, owned by Sail Bahrain, is called the Kingdom of Bahrain, according to a diplomatic source and Sail Bahrain's Web site.